1. Field of the Invention
The present invention relates to an operation unit for a construction machine, the operation unit comprising a floor, an operation seat provided on the floor and a console box provided on a lateral side of the operation seat. The present invention also relates to a hose cover for covering respective over-floor portions of a plurality of hoses connected to a pilot valve within the console box, i.e., a portion of the hose from the floor to the console box.
2. Description of the Background Art
The background art of the present invention will be described by taking a hydraulic shovel as an example.
A hydraulic shovel generally comprises a crawler-type lower propelling body, an upper slewing body mounted on the lower propelling body, and a working attachment attached to the upper slewing body, wherein the upper slewing body is provided with an operation unit.
FIGS. 10 and 11 show an upper slewing body of a hydraulic shovel, which is an open type having an operation unit exposed to the outside. This operation unit comprises a floor F, an operation seat 1 provided above the floor F, and two console boxes 2, 3 provided on left and light sides of the operation seat 1, respectively; each of the console boxes 2, 3 is provided with a working manipulation device comprising a control lever 4 and a pilot valve 5 adapted to be operated by the control lever 4. Furthermore, a control lever 6 and a pedal 7 are provided on the floor F at a position in front of the operation seat 1.
As used in this specification, the terms “front (frontward)”, “rear (rearward)”, “right (rightward)” and “left (leftward)” mean respective directions as seen from an operator seated in the operation seat 1.
The left console box 2 of the two console boxes 2 and 3, which is so positioned as to face an entrance, is disposed so as to prevent the console box 2, particularly the control lever 4 thereof, from disturbing getting-on or getting-off operators. Specifically, the console box 2 is supported rotationally movably about a pivot shaft 8 shown in FIG. 11, between a lowered position for a working mode, indicated by the solid line in FIG. 11, and a lifted position for a getting-on/off mode, indicated by the two-dot chain line in FIG. 11. The lifted position is located upward and rearward of the lowered position to open up the entrance. The console box 2 is set to the lifted position during getting-on/off.
There is provided a gate lever 9 on a left front side of the operation seat 1. The gate lever 9 is able to be swung in a frontward-rearward direction, like a barrier for a railroad crossing, to open and close the entrance. Specifically, the gate lever 9 is operated so as to close the entrance during working and open the entrance during getting-on/off. The gate lever 9 is generally coupled to the left console box 2 through an interlocking mechanism for interlocking between the gate lever 9 and the console box 2, thus being automatically opened and closed interlockingly with lifting and lowering of the console box 2.
The operation unit further comprises a plurality of hoses. Each of the hoses has one end connected to the pilot valve 5 within the left console box 2 and the other end connected to a control valve, a pump and a tank provided at a position away from the pilot valve 5, e.g., in an equipment compartment on a right side of the upper slewing body. On the floor F is provided a hose guide 11, which is formed in a tubular shape to guide each of the hoses from the upper side of the floor F to the lower side thereof.
The hoses are usually arranged between the pilot valve 5 and the control valve while being hidden by passing inside a seat stand supporting the operating seat 1 from therebelow and under the floor F; however, in the operation unit where the seat stand does not exist underneath the left console box 2 as illustrated in FIGS. 10 and 11, the hoses are exposed between the console box 2 and the floor F. Accordingly, in view of improving visual quality and preventing oil from littering due to hose breakage, it is desirable to cover a plurality of over-floor portions 10 which are respective portions of the hoses between the pilot valve 5 and the floor F.
FIGS. 10 and 11 illustrate only two of the over-floor portions 10, for the sake of simplification, while the number thereof is typically six.
Heretofore, as a structure for covering a hydraulic piping including hoses, there have been known a first technique disclosed in Japanese Patent Laid-Open Publication No. 2010-90589 and a second technique disclosed in Japanese Utility Model Laid-Open Publication No. 06-12557. In the first conventional technique, a halved cylindrical-shaped casing or a bellows-like member covers hoses as a cover member. In the second conventional technique, a rectangular-shaped cloth is wrapped around hoses as a cover member and held in a cylindrical shape by a tape fastener or the like. However, these conventional techniques have the following problems.
The first conventional technique, using the casing or the bellows-like member as a cover member, involves a high cost. Moreover, in the case of using the cover member for covering the over-floor portions 10, mechanical vibration may bring an inner surface of the cover member, which is generally given an inner diameter set to a relatively large value enough to loosely cover the over-floor portions 10, into intermittent contact with the over-floor portions 10, which may cause the cover member or the over-floor portions 10 to be damaged. Particularly, a rotationally movable console box such as the box 2 shown in FIGS. 10 and 11 makes a rotational movement which can cause the over-floor portions 10 to bend and stretch while strongly rubbing against the inner surface of the cover member; this increases a risk of the damage.
On the other hand, in the case of utilizing the second conventional technique to cover the over-floor portions 10, it is difficult to obtain good visual quality. Specifically, the over-floor portions 10 form a hose bundle which has an upper region including a connection area with the pilot valve 5 and a lower region close to the floor F, wherein the upper region has a large diameter while the lower region has a small diameter. Hence, if a large diameter is given to the entire cover member in conformity to the diameter of the upper region, the cover member may slack in its lower section, which causes deterioration in visual quality. Inversely, if a small diameter is given to the cover member in its wrapped state in order to suppress the occurrence of the slack, the bending and stretching movement of the over-floor portions 10 involved by the rotational movement of the console box applies a mechanical load, particularly, to an interconnection portion, that is, a portion where both wrapping ends of an upper section of the cover member are interconnected; this results in the possibility that the interconnection of the wrapping ends is released.